Support gpio

Author: arn0

cores/esp32/Arduino.h

@@ -33,6 +33,7 @@
 #include "freertos/FreeRTOS.h"
 #include "freertos/task.h"
 #include "freertos/semphr.h"
+#include "driver/gpio.h"
 //--//#include "esp32-hal.h"
 //--//#include "esp8266-compat.h"
 //--//#include "soc/gpio_reg.h"